Schedule of Earnings per Share, Basic and Diluted [Line Items]

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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-Subparagraph (SX 210.4-08.(i)(4))
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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.4-08.(i)(2))
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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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-Publisher FASB
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

The per share price of the Company's stock at which the contract holder of the freestanding contract has the right to purchase or sell the Company's stock at a future date.

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-Publisher FASB
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- Definition

Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

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- Definition

The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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Earnings (Loss) per Share (Narrative) (Details)	1 Months Ended			3 Months Ended		6 Months Ended
Earnings (Loss) per Share (Narrative) (Details)	Jun. 30, 2016 USD ($) $ / shares	Jan. 31, 2015 $ / shares	Jun. 30, 2012 $ / shares shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2015 shares	Jun. 30, 2016 USD ($) $ / shares shares	Jun. 30, 2015 shares
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)					1,463,326		1,608,762
Shares issuable upon conversion, included in diluted shares (in shares)				2,798,000	0	2,848,000	0
Convertible Senior Notes Due 2023 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio	0.0204198
Conversion price (USD per share) \| $ / shares	$ 48.97			$ 48.97		$ 48.97
Convertible Senior Notes Due 2022 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio		0.0298806
Conversion price (USD per share) \| $ / shares		$ 33.47
Shares issuable upon conversion, included in diluted shares (in shares)				605,658		302,829
Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Conversion ratio			0.0358038
Conversion price (USD per share) \| $ / shares			$ 27.93
Shares issuable upon conversion, included in diluted shares (in shares)				409,193		917,449
Debt, aggregate principal amount repurchased \| $	$ 220,000,000			$ 220,000,000		$ 220,000,000
Convertible Senior Notes Due 2017 [Member] \| Senior Notes [Member] \| 2017 Warrants [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Shares issuable upon conversion, included in diluted shares (in shares)				59,013		29,506
Warrants for shares of common stock (shares)			1,960,000
Strike price, warrant (USD per share) \| $ / shares			$ 34.20
Stock options [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				3,102,640		3,199,586
Unvested restricted stock [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Antidilutive shares excluded from computation of diluted loss per share (shares)				27,408		13,704
Call Option [Member] \| Convertible Senior Notes Due 2023 [Member] \| Senior Notes [Member]
Schedule of Earnings per Share Basic and Diluted [Line Items]
Strike price, capped calls (USD per share) \| $ / shares	$ 48.97
Cap price (USD per share) \| $ / shares	$ 64.68